This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. Benign-Malignant Lesion Differentiation Using Functional ADC-Thresholding [unreadable]Allowing Expert Radiologist Interpretation [unreadable] Versus Conventional Thresholding Based On ADC Cut-Off Values Diffusion-weighted imaging (DWI) may aid in the discrimination of benign from malignant (breast) lesions. Approaches to benefit from the information contained in the DWI dataset have mostly been based on trying to define a cut-off value for the lesion ADC. This may be limiting because of the relatively low SNR, the relatively high variability of lesion ADC - even within one hospital or patient population - and the limited potential of the results to be extrapolated to different field strengths, pulse-sequences or b-values. We used an approach in which the high CNR of DWI and the quantitative information of the ADC are presented to the radiologist in a "functionally-thresholded ADC (ftADC) map" that increases the conspicuity of lesions of interest, much like phase-images are used to increase vascular conspicuity in susceptibility- weighted imaging. Radiologists can "window-level" ftADC-maps at their discretion and diagnose a lesion as "ftADC-bright" without having to choose an ADC-threshold value;Similar to, for example, a cystic lesion being interpreted as "T2-bright" without using T2-cut-off values. We performed a retrospective, HIPAA-compliant, IRB-approved analysis of DW data sets of 103 consecutive women who underwent 1.5T MRI for the evaluation of breast cancer. Conventional ADC-thresholding was compared to ftADC-mapping and to dynamic contrast-enhanced (DCE) MRI, for all pathology-verified lesions. To read about other projects ongoing at the Lucas Center, please visit http://rsl.stanford.edu/ (Lucas Annual Report and ISMRM 2011 Abstracts)